Inconsistency in README for version pinning

[rwohleb]

Found a bug? Maybe our Slack Community can help.

Describe the Bug

The README usage section says to use version to pin the atmos version, but the input section then gives atmos-version (which matches with action.yml). To make things more confusing, the docs on the website say to use atmos_version (underscore instead of dash).

Expected Behavior

Consistency in the documentation for input variables.

Steps to Reproduce

Steps to reproduce the behavior:

1. Go to '...'
2. Run '....'
3. Enter '....'
4. See error

Screenshots

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Environment (please complete the following information):

Anything that will help us triage the bug will help. Here are some ideas:

• OS: [e.g. Linux, OSX, WSL, etc]
• Version [e.g. 10.15]

Additional Context

Add any other context about the problem here.

[jasonwashburn]

Added a PR to address this #104